The hip-hop-themed musical Hamilton has become the breakout hit on Broadway, but now it’s caught up in some controversy over a casting call notice.

According to CBS New York, civil rights attorney Randolph McLaughlin, of the Newman Ferrara Law Firm, has accused the Hamilton producers of discriminatory practices for their casting notice, which specified that the show was seeking “non-white” performers. He believes that the ad may violate the New York City Human Rights Law that forbids discrimination in hiring based on race.

For those who haven’t seen Hamilton, it is a musical about Alexander Hamilton, written by Lin-Manuel Miranda, and boasts a diverse cast of black and Latino actors portraying the Founding Fathers except for King George who is played by a white actor. The play has been praised for its ethnic diversity but McLaughlin feels they have crossed the line with the casting ad.

“What if they put an ad out that said, ‘Whites only need apply? Why, African-Americans, Latinos, Asians would be outraged,” he told CBS New York.

Broadway producer Jeffrey Seller and his fellow Hamilton producers deny any wrongdoing in a statement that reads in part, “The producers of Hamilton regret the confusion that’s arisen from the recent posting of an open call casting notice for the show. It is essential to the storytelling of Hamilton that the principal roles ­–which were written for non-white characters (excepting King George) – ­­be performed by non-white actors. This adheres to the accepted practice that certain characteristics in certain roles constitute a “bona fide occupational qualification” that is legal.”

“This also follows in the tradition of many shows that call for race, ethnicity or age specific casting, whether it’s The Color Purple or Porgy & Bess or Matilda. The casting will be amended to also include language we neglected to add, that is, we welcome people of all ethnicities to audition for Hamilton.”

Since then, the latest Hamilton casting ads do reflect the changes with the wording, “Performers of all ethnic and racial backgrounds are encouraged to attend.”